Apparatuses for controlling a motor installed in an electrical actuator system, such as an electric power steering system, usually have a function of avoiding an overcurrent from being supplied to the motor.
For example, Japanese Patent Publication No. 5109554, referred to as a published patent document, discloses a motor control apparatus installed in a motor system in which a voltage from a power source is supplied to a motor via an inverter. The motor control apparatus is configured to limit, based on the voltage from the power source and the rotational angular velocity of the motor, a current, which is supplied from the power source to flow through the inverter as an inverter current, to be equal to or lower than a predetermined allowable upper limit.